I’m surprised they’ve introduced four M1 variants already, and while that makes a fifth variant seem more likely… I still think they’ll want to find another way to differentiate the new Mac Pro. What seems more likely to me: the M2 MBA is released either in tandem with a M2 Ultra MP, or a few months ahead of it, and the other higher spec models will lag 6-12 months behind from then on. Especially given the significant delays on M1 Max, it makes sense to me they’ll want to roll out the next gen in a lower volume/higher margin while they ramp up production.
re: four M1 variants, the clever thing is that from a certain perspective, they've only designed two. It's just that one of those two (M1 Max) was designed such that it could be scaled down down to M1 Pro and up to M1 Ultra.
On scaling down, they simply designed and laid out M1 Max such that half the GPU cores, memory controllers, and media encoders were divisible from the rest of the chip, with the interface between the two a clean, straight cut line. To make M1 Pro masks, they likely just took the M1 Max mask artwork, cropped it, and did minor cleanup on the cropped edge to terminate all the dangling connections.
To make M1 Ultra, they just "glue" two M1 Max die together with advanced packaging and interconnect technology. Every M1 Max ships with an unused die-to-die interconnect block along one edge of the chip.